The present invention relates to the use of low amplitude vibrations in the seismic frequency range for enhancing the recovery of oil from subterranean, viscous oil-containing formations employing a gaseous driving fluid such as carbon dioxide to drive the oil from the formation.
Sonic energy has been used for increasing the recovery of oil from an oil-bearing formation employing fluid drive, such as water flooding, gas drive, and the like, as shown in the patent to Sherborne, U.S. Pat. No. 2,670,801. The Sherborne process discloses the use of sonic or supersonic vibrations impressed upon an oil-bearing formation prior to and/or during a liquid flooding or gas driving recovery process to enhance the efficiency.
The patent to Bodine, U.S. Pat. No. 2,700,422, discloses the use of sonic vibrations in the frequency range of 10 to 30 cps for enhancing the recovery of oil from oil-containing formations in conjunction with a liquid driving fluid for sweeping oil from the formation.
The patent to Holloway, Jr., U.S. Pat. No. 3,754,598, discloses an enhanced flooding fluid process for the secondary recovery of oil from oil-containing formations wherein during the recovery operation oscillating pressure waves are transmitted from the injection well through the formation having a preselected amplitude in the range of about 10 to 5,000 psi above the formation pressure and a frequency in the range of about 0.001 to about 25 cycles per second.
In addition, other patents of interest are U.S. Pat. No. 3,189,536 to Bodine; U.S. Pat. No. 3,520,362 to Galle; U.S. Pat. No. 3,527,300 to Phillips; U.S. Pat. No. 3,952,800 to Bodine; and U.S. Pat. No. 4,060,128 to Wallace.